Organic light-emitting display apparatus and method of manufacturing the same

ABSTRACT

An organic light-emitting display apparatus including a substrate, a first first electrode on the substrate, a first organic functional layer on the first first electrode, the first organic functional layer including a first emission layer, a first second electrode on the first organic functional layer, a second first electrode on the substrate, the second first electrode being spaced apart from the first first electrode, a second organic functional layer on the second first electrode, the second organic functional layer including a second emission layer, a second second electrode on the second organic functional layer, and a self-assembled layer between the first organic functional layer and the second organic functional layer, the self-assembled layer containing fluorine.

CROSS-REFERENCE TO RELATED APPLICATION

Korean Patent Application No. 10-2017-0030982, filed on Mar. 13, 2017,in the Korean Intellectual Property Office, and entitled: “OrganicLight-Emitting Display Apparatus and Method of Manufacturing the Same,”is incorporated by reference herein in its entirety.

BACKGROUND 1. Field

One or more embodiments relate to an organic light-emitting displayapparatus and a method of manufacturing the organic light-emittingdisplay apparatus.

2. Description of the Related Art

An organic light-emitting display apparatus is a self-emitting displayapparatus that includes a hole injection electrode, an electroninjection electrode, and an organic emission layer formed between thehole injection electrode and the electron injection electrode; and emitslight when holes injected from the hole injection electrode andelectrons injected from the electron injection electrode recombine inthe organic emission layer. The organic light-emitting display apparatushas advantages such as low power consumption, high luminance, and fastresponse, and thus has received attention as a next-generation displayapparatus.

SUMMARY

Embodiments are directed to an organic light-emitting display apparatusincluding a substrate, a first first electrode on the substrate, a firstorganic functional layer on the first first electrode, the first organicfunctional layer including a first emission layer, a first secondelectrode on the first organic functional layer, a second firstelectrode on the substrate, the second first electrode being spacedapart from the first first electrode, a second organic functional layeron the second first electrode, the second organic functional layerincluding a second emission layer, a second second electrode on thesecond organic functional layer, and a self-assembled layer between thefirst organic functional layer and the second organic functional layer,the self-assembled layer containing fluorine.

A color of light emitted from the first emission layer may be differentfrom a color of light emitted from the second emission layer.

Each of the first organic functional layer and the second organicfunctional layer may further include at least one of a hole injectionlayer, a hole transport layer, an electron transport layer, and anelectron injection layer.

The organic light-emitting display apparatus may further include apixel-defining layer including an insulating layer and covering an edgeof the first first electrode and an edge of the second first electrode.

An edge portion of the first organic functional layer and an edgeportion of the second organic functional layer may be on an inclinedsurface of the pixel-defining layer.

The self-assembled layer may be on the pixel-defining layer and maysurround the first organic functional layer and the second organicfunctional layer.

The self-assembled layer may be spaced apart from end portions of thefirst organic functional layer and the second organic functional layerby a preset gap.

The self-assembled layer may be under the pixel-defining layer and maysurround peripheries of the first first electrode and the second firstelectrode.

The self-assembled layer may overlap end portions of the first firstelectrode and the second first electrode.

The self-assembled layer may include a fluorocarbon group (—CF₃).

The first first electrode and the second first electrode may include aconductive oxide.

The first first electrode and the second first electrode may include atleast one of indium tin oxide, indium zinc oxide, zinc oxide, indiumoxide, indium gallium oxide, and aluminum zinc oxide.

The organic light-emitting display apparatus may further include acommon electrode integrally formed on the first second electrode and thesecond second electrode.

Embodiments are also directed to a method of manufacturing an organiclight-emitting display apparatus including forming a first firstelectrode and a second first electrode on a substrate so as to be spacedapart from each other, forming a self-assembled layer containingfluorine on the first first electrode and the second first electrode,sequentially forming a first lift-off layer and a first photoresist onthe self-assembled layer, removing a portion of the first lift-off layerand a portion of the first photoresist in an area corresponding to thefirst first electrode and allowing the self-assembled layer to remain,removing a portion of the self-assembled layer on the first firstelectrode by performing first plasma heat treatment, and sequentiallyforming, on the first first electrode, a first organic functional layerand a first second electrode, wherein the first organic functional layerincludes a first emission layer, and lifting off a remaining portion ofthe first lift-off layer.

The first lift-off layer may have a fluorine content ranging from 20 wt% to 60 wt %.

The first organic functional layer and the first second electrode may beformed by a deposition process.

Removing the portion of the first photoresist may include performing aphotolithography process.

The first lift-off layer may be etched and removed by using a firstsolvent containing fluorine.

The self-assembled layer may be formed by a vapor deposition method.

The self-assembled layer may include a hydrolyzable reactive group and afluorine-containing functional group.

The method may further include sequentially forming a second lift-offlayer and a second photoresist after lifting off the remaining portionof the first lift-off layer, removing a portion of the second lift-offlayer and a portion of the second photoresist in an area correspondingto the second first electrode and allowing the self-assembled layer toremain removing a portion of the self-assembled layer on the secondfirst electrode by performing second plasma heat treatment, sequentiallyforming a second organic functional layer and the second secondelectrode on the second first electrode, wherein the second organicfunctional layer includes a second emission layer, and lifting off aremaining portion of the second lift-off layer.

The method may further include forming, between the first firstelectrode and the second first electrode, a pixel-defining layerincluding an insulating layer.

The self-assembled layer may be formed on the pixel-defining layer.

The self-assembled layer may be formed under the pixel-defining layer.

The method may further include forming a common electrode in an integralform on the first second electrode and the second second electrode.

Embodiments are also directed to a method of manufacturing an organiclight-emitting display apparatus, including forming a first firstelectrode and a second first electrode on a substrate so as to be spacedapart from each other, forming a first self-assembled layer on the firstfirst electrode and the second first electrode, forming a firstphotoresist on the first self-assembled layer, removing a portion of thefirst photoresist in an area corresponding to the first first electrodeand allowing the first self-assembled layer to remain, removing aportion of the first self-assembled layer on the first first electrodeby performing first plasma heat treatment, and sequentially forming afirst organic functional layer and a first second electrode on the firstfirst electrode. The first organic functional layer includes a firstemission layer, and lifting off a remaining portion of the firstphotoresist and a remaining portion of the first self-assembled layer.

BRIEF DESCRIPTION OF THE DRAWINGS

Features will become apparent to those of skill in the art by describingin detail exemplary embodiments with reference to the attached drawingsin which:

FIG. 1 illustrates a cross-sectional view of an organic light-emittingdisplay apparatus according to an embodiment;

FIG. 2 illustrates a plan view of a portion of the organiclight-emitting display apparatus according to the embodiment illustratedin FIG. 1;

FIG. 3 illustrates a cross-sectional view for explaining forming aplurality of anodes on a substrate of the organic light-emitting displayapparatus according to the embodiment illustrated in FIG. 1;

FIG. 4 illustrates a cross-sectional view for explaining forming apixel-defining layer in the organic light-emitting display apparatusaccording to the embodiment illustrated in FIG. 1;

FIGS. 5A to 5F illustrate cross-sectional views for explaining stages ofa first unit process of forming the organic light-emitting displayapparatus according to the embodiment illustrated in FIG. 1;

FIGS. 6A to 6F illustrate cross-sectional views for explaining stages ofa second unit process of forming the organic light-emitting displayapparatus according to the embodiment illustrated in FIG. 1;

FIGS. 7A to 7F illustrate cross-sectional views for explaining stages athird unit process of forming the organic light-emitting displayapparatus according to the embodiment illustrated in FIG. 1;

FIG. 8 illustrates a cross-sectional view of an organic light-emittingdisplay apparatus according to an embodiment;

FIG. 9 illustrates a plan view of a portion of the organiclight-emitting display apparatus according to the embodiment illustratedin FIG. 8;

FIG. 10 illustrates a cross-sectional view for explaining an operationof forming a plurality of anodes and a self-assembled monolayer on asubstrate of the organic light-emitting display apparatus according tothe embodiment illustrated in FIG. 8;

FIG. 11 illustrates a cross-sectional view for explaining forming apixel-defining layer in the organic light-emitting display apparatusaccording to the embodiment illustrated in FIG. 8;

FIGS. 12A to 12F illustrate cross-sectional views for explaining stagesof a first unit process of forming the organic light-emitting displayapparatus according to the embodiment illustrated in FIG. 8;

FIGS. 13A to 13F illustrate cross-sectional views for explaining stagesof a second unit process of forming the organic light-emitting displayapparatus according to the embodiment illustrated in FIG. 8;

FIGS. 14A to 14F illustrate cross-sectional views for explaining a thirdunit process of forming the organic light-emitting display apparatusaccording to the embodiment illustrated in FIG. 8;

FIGS. 15A to 15E illustrate cross-sectional views for explaining a firstunit process of forming an organic light-emitting display apparatusaccording to an embodiment;

FIGS. 16A to 16E illustrate cross-sectional views for explaining asecond unit process of forming the organic light-emitting displayapparatus following the first unit process illustrated in FIGS. 15A to15E according to an embodiment;

FIGS. 17A to 17E illustrate cross-sectional views for explaining a thirdunit process of forming the organic light-emitting display apparatusfollowing the second unit process illustrated in FIGS. 16A to 16Eaccording to an embodiment;

FIGS. 18A to 18E illustrate cross-sectional views for explaining a firstunit process of forming an organic light-emitting display apparatusaccording to a comparative example;

FIGS. 19A to 19E illustrate cross-sectional views for explaining asecond unit process of the organic light-emitting display apparatusaccording to the comparative example;

FIGS. 20A to 20E illustrate cross-sectional views for explaining a thirdunit process of the organic light-emitting display apparatus accordingto the comparative example; and

FIG. 21 illustrates a diagram illustrating an operation mechanism of aself-assembled monolayer.

DETAILED DESCRIPTION

Example embodiments will now be described more fully hereinafter withreference to the accompanying drawings; however, they may be embodied indifferent forms and should not be construed as limited to theembodiments set forth herein. Rather, these embodiments are provided sothat this disclosure will be thorough and complete, and will fullyconvey exemplary implementations to those skilled in the art.

In the drawing figures, the dimensions of layers and regions may beexaggerated for clarity of illustration. It will also be understood thatwhen a layer or element is referred to as being “on” another layer orsubstrate, it can be directly on the other layer or substrate, orintervening layers may also be present. Further, it will be understoodthat when a layer is referred to as being “under” another layer, it canbe directly under, and one or more intervening layers may also bepresent. In this regard, unless otherwise provided, a description that alayer or element is “under” another layer or element may be interpretedas indicating that the layer or element is closer to the substrate thanthe other layer or element. In addition, it will also be understood thatwhen a layer is referred to as being “between” two layers, it can be theonly layer between the two layers, or one or more intervening layers mayalso be present. Like reference numerals refer to like elementsthroughout.

FIG. 1 illustrates a cross-sectional view of an organic light-emittingdisplay apparatus 1 according to a an embodiment, and FIG. 2 illustratesa plan view of a portion of the organic light-emitting display apparatus1 according to the embodiment.

Referring to FIGS. 1 and 2, in the organic light-emitting displayapparatus 1, a plurality of anodes including a first anode 101, a secondanode 102, and a third anode 103 may be on a substrate 100 in a spacedapart relationship each other.

First to third organic functional layers 141, 142, and 143 includingfirst to third emission layers may be respectively located on the firstto third anodes 101, 102, and 103. First to third auxiliary cathodes181, 182, and 183 including a conductive material may be respectivelylocated on the first to third organic functional layers 141, 142, and143. An integrally formed common electrode 180 may be located on thefirst to third auxiliary cathodes 181, 182, and 183. (The firstauxiliary cathode 181, the second auxiliary cathode 182, and the thirdauxiliary cathode 183 may also be referred to as a first secondelectrode, a second second electrode and a third second electrode, so asto not be limited as to polarity. For example, in some implementations,electrodes 101,102, and 103 may be cathodes, and electrodes 180, 181,182, and 183 may be anodes.)

A pixel-defining layer 110 including an insulating material may coverend portions of the first to third anodes 101, 102, and 103. Thepixel-defining layer 110 may prevent electric field concentration ateach of the end portions of the first to third anodes 101, 102, and 103.

A self-assembled monolayer 150 may be located on the pixel-defininglayer 110. The self-assembled monolayer 150 may surround the first tothird organic functional layers 141, 142 and 143. The self-assembledmonolayer 150 may be spaced apart from the end portions of the first tothird organic functional layers 141, 142, 413 by a predetermineddistance D1.

The self-assembled monolayer 150 may include a fluorine-containingfunctional group and a hydrolyzable reactive group.

The fluorine-containing functional group may include fluorocarbon(—CF₃). The hydrolyzable reactive group may include a silicone compound.For example, the self-assembled monolayer 150 may include FOTS(1H,1H,2H,2H-perfluorodecyltrichlorosilane-perfluoro), FDTS(heptadecafluoro-1,1,2,2,-tetrahydrodecyl)trichlorosilane), FOMMS(CF₃(CF₂)₅(CH₂)₂Si(CH₃)₂Cl), FOMDS (CF₃(CF₂)₅(CH₂)₂Si(CH₃)Cl₂), FOTES(CF₃(CF₂)₅(CH₂)₂Si(OC₂HO₃), or the like.

The self-assembled monolayer may include a hydrophobic functional groupcontaining a methyl group (—CH). For example, the self-assembledmonolayer may include octadecyltrichlorosilane (OTS),dichlorodimethylsilane (DDMS), or the like.

The fluorine-containing functional group may be located at a greaterdistance from the surfaces of the first to third anodes 101, 102, and103 and the pixel-defining layer 110 than the hydrolyzable reactivegroup. The fluorine-containing functional group of the self-assembledmonolayer 150 may have a small difference in surface energy with respectto a lift-off layer 121 (see FIG. 5A) containing fluorine, to bedescribed below. Thus, the lift-off layer 121 may be uniformly formed onthe self-assembled monolayer 150, thereby improving patterningprecision. In addition, the term “monolayer” used in the self-assembledmonolayer is not limited as meaning that the self-assembled monolayerincludes a single molecule. Herein, instead of the term “self-assembledmonolayer”, the term “self-assembled layer” may be used as having thesame meaning as the term “self-assembled monolayer”.

With reference to FIGS. 3 to 7F, a method of manufacturing the organiclight-emitting display apparatus 1 and the organic light-emittingdisplay apparatus 1 manufactured by the above method are described inmore detail.

FIG. 3 illustrates a cross-sectional view for explaining forming thefirst to third anodes 101, 102, and 103 on the substrate 100 of theorganic light-emitting display apparatus 1. FIG. 4 illustrates across-sectional view for explaining forming the pixel-defining layer 110in the organic light-emitting display apparatus 1. FIGS. 5A to 5Fillustrates cross-sectional views for explaining a first unit process offorming the organic light-emitting display apparatus 1. FIGS. 6A to 6Fillustrate cross-sectional views for explaining a second unit process ofthe organic light-emitting display apparatus 1. FIGS. 7A to 7Fillustrate cross-sectional views for explaining a third unit process ofthe organic light-emitting display apparatus 1.

Referring to FIG. 3, a plurality of anodes including the first anode101, the second anode 102, and the third anode 103 may be formed on thesubstrate 100. (The first anode 101, the second anode 102, and the thirdanode 103 may also be referred to as a first first electrode, a secondfirst electrode and a third first electrode, so as to not be limited asto polarity.)

The substrate 100 may include suitable materials. For example, thesubstrate 100 may include glass or plastic. Examples of the plastic mayinclude materials having excellent heat resistance and excellentdurability, such as polyimide, polyethylenenaphthalate,polyethyleneterephthalate, polyarylate, polycarbonate, polyetherimide,and polyethersulfone.

A buffer layer for flattening a top surface of the substrate 100 andpreventing penetration of impurities may be further formed on thesubstrate 100. For example, the buffer layer may be a single layer or aplurality of layers including silicon nitride, silicon oxide, and/or thelike.

The first to third anodes 101, 102, and 103 may be hole injectionelectrodes and may include materials having a high work function. Thefirst to third anodes 101, 102, and 103 may each include a transparentconductive oxide component. For example, the first to third anodes 101,102, and 103 may include at least one selected from indium tin oxide,indium zinc oxide, zinc oxide, indium oxide, indium gallium oxide, andaluminum zinc oxide. The first to third anodes 101, 102, and 103 mayeach be a single layer or may be a plurality of layers including a metaland/or an alloy such as silver (Ag), aluminum (Al), magnesium (Mg),lithium (Li), or calcium (Ca).

The first to third anodes 101, 102, and 103 may electrically contactfirst to third thin-film transistors, respectively, that are locatedbetween the substrate 100 and the first to third anodes 101, 102, and103.

Referring to FIG. 4, the pixel-defining layer 110 surrounding edges ofthe first anode 101, the second anode 102, and the third anode 103 maybe formed on the substrate 100.

End portions of the first to third anodes 101, 102, and 103 may besharp. Accordingly, when a current is applied after the first to thirdauxiliary cathodes 181, 182, and 183 are formed, there is a possibilitythat an electric field could concentrate on the end portions of thefirst to third anodes 101, 102, and 103, and thus an electrical shortcircuit could occur during operation. However, when the end portions ofthe first to third anodes 101, 102, and 103 are covered by thepixel-defining layer 110, as illustrated in FIGS. 1 and 4, an electricfield may be prevented from concentrating at the end portions of thefirst to third anodes 101, 102, and 103.

The pixel-defining layer 110 may be an organic insulating layerincluding, for example, a general-purpose polymer such as poly(methylmethacrylate) (PMMA) or polystyrene (PS), a polymer derivative having aphenol group, an acryl-based polymer, an imide-based polymer, anarylether-based polymer, an amide-based polymer, a fluorine-basedpolymer, a p-xylene-based polymer, a vinyl alcohol-based polymer, or ablend thereof.

Referring to FIG. 5A, a self-assembled monolayer 150, a first lift-offlayer 121, and a first photoresist 131 are sequentially formed on thesubstrate 100 on which the first to third anodes 101, 102, and 103 areformed.

The self-assembled monolayer 150 may be formed by using a coatingmethod, a printing method, a deposition method, or the like. Theself-assembled monolayer 150 may include a fluorine-containingfunctional group and a hydrolyzable reactive group, as described above.For example, as described above, the self-assembled monolayer 150 mayincludes FOTS (1H,1H,2H,2H-perfluorodecyltrichlorosilane-perfluoro),FDTS (heptadecafluoro-1,1,2,2,-tetrahydrodecyl)trichlorosilane), FOMMS(CF₃(CF₂)5(CH₂)₂Si(CH₃)₂Cl), FOMDS (CF₃(CF₂)₅(CH₂)₂Si(CH₃)Cl₂), FOTES(CF₃(CF₂)₅(CH₂)₂Si(OC₂H₅)₃), or the like.

The first lift-off layer 121 may include a fluoropolymer. Thefluoropolymer included in the first lift-off layer 121 may include apolymer having a fluorine content ranging from about 20 wt % to about 60wt %. For example, the fluoropolymer included in the first lift-offlayer 121 may include at least one from among a copolymer ofpolytetrafluoroethylene, polychlorotrifluoroethylene,polydichlorodifluoroethylene, chlorotrifluoroethylene, anddichlorofluoroethylene, a copolymer of tetrafluoroethylene andperfluoroalkylvinylether, a copolymer of chlorotrifluoroethylene andperfluoroalkylvinylether, a copolymer of tetrafluoroethylene andperfluoroalkylvinylether, and a copolymer of chlorotrifluoroethylene andperfluoroalkylvinylether.

The first lift-off layer 121 may be formed by using a coating method, aprinting method, a deposition method, or the like. When the firstlift-off layer 121 is formed by using a coating method or a printingmethod, curing and polymerization may be performed as desired, and thena process of forming a first photoresist 131 may be performed.

FIG. 21 schematically illustrates a mechanism by which a self-assembledmonolayer 150 may operate when the self-assembled monolayer 150 isformed on a first anode 101.

For example, when a self-assembled monolayer 150 including FOTS isdeposited on a first anode 101 including indium tin oxide, a hydrolysisreactive group that includes silicon, of the self-assembled monolayer150, may cause a hydrolysis and condensation reaction with a hydroxylgroup (—OH) of the surface of the first anode 101. The self-assembledmonolayer 150 may be covalently bonded to the surface of the first anode101. This covalent bonding may increase adhesion between the surface ofthe self-assembled monolayer 150 and the surface of the first anode 101.

When a first lift-off layer 121 including a fluoropolymer is formed onthe self-assembled monolayer 150, a fluorine-containing functional groupof the self-assembled monolayer 150, which is in close contact with thefirst lift-off layer 121, may have a small difference in surface energywith respect to the lift-off layer 121. Thus, the lift-off layer 121 maybe uniformly formed on the self-assembled monolayer 150.

The first photoresist 131 may be formed on the first lift-off layer 121.As illustrated in FIG. 5A, the first photoresist 131 at a positioncorresponding to the first anode 101 may be exposed through a firstphotomask M1 including an area M11 through which light L is transmitted.

Referring to FIG. 5B, the first photoresist 131 may be developed. Thefirst photoresist 131 may be a positive photoresist or a negativephotoresist. In the present embodiment, it is assumed that the firstphotoresist 131 is a positive photoresist. In the first photoresist 131that is developed, a first portion 131-1 corresponding to the firstanode 101 may be removed and a second portion 131-2 other than the firstportion 131-1 may remain.

Referring to FIG. 5C, the first lift-off layer 121 may be etched byusing a pattern of the first portion 131-1 of the first photoresist 131as an etch mask.

The first lift-off layer 121 may include the fluoropolymer. Accordingly,a solvent that etches the fluoropolymer may be used as an etchant.

A first solvent including fluorine may be used as the etchant. The firstsolvent may include hydrofluoroether, which is a material that iselectrochemically stable due to a low interaction with other materialsand is environmentally stable due to a low global warming potential anda low toxicity.

A portion of the first lift-off layer 121 formed at a positioncorresponding to the first portion 131-1, that is, above the first anode101, may be etched during an etching process. The first lift-off layer121 may be etched by the first solvent including fluorine to form afirst undercut profile UC1-1 under a boundary surface of the firstportion 131-1 of the first photoresist 131.

The self-assembled monolayer 150 may be well bonded to the top surfaceof the first anode 101 while the first lift-off layer 121 is etched. Forexample, as described above, a hydrolysis and condensation reaction mayoccur between a reactive group including silicon, included in theself-assembled monolayer 150, and the surface of the first anode 101. Anadhesive strength due to covalent bonding between the self-assembledmonolayer 150 and the surface of the first anode 101 may be increased.

In addition, a hydrolysis and condensation reaction may occur between areactive group including silicon, included in the self-assembledmonolayer 150, and a surface material of the pixel-defining layer 110,and thus an adhesive strength between the surface of the self-assembledmonolayer 150 and the surface of the pixel-defining layer 110 may beincreased. The self-assembled monolayer 150 may be well bonded to thetop surface of the pixel-defining layer 110 while the first lift-offlayer 121 is etched.

Referring to FIG. 5D, a portion of the self-assembled monolayer 150 onthe first anode 101 may be removed by performing first plasma heattreatment on the structure illustrated in FIG. 5C.

The Si—O bond between the first anode 101 and the self-assembledmonolayer 150 shown in FIG. 21 may be cleanly broken by the first plasmaheat treatment. In this regard, if the first lift-off layer 121 were tobe directly formed on the first anode 101 after the formation of thefirst anode 101 without forming the self-assembled monolayer 150 andwere to be removed in a subsequent process, a residue of the firstlift-off layer 121 could remain on the first anode 101, causingcontamination. However, in the present embodiment, the self-assembledmonolayer 150 may be formed between the first anode 101 and the firstlift-off layer 121 to prevent a residue of the first lift-off layer 121from remaining on the first anode 101, thereby preventing deteriorationof the organic-light emitting display apparatus.

Referring to FIG. 5E, a first organic functional layer 141 including afirst emission layer and a first auxiliary cathode 181 may besequentially formed on the structure illustrated in FIG. 5D.

The first organic functional layer 141 may further include at least oneselected from a hole injection layer, a hole transport layer, anelectron transport layer, and an electron injection layer.

The first organic functional layer 141 may be formed by a vacuumdeposition method. In the deposition process, the first lift-off layer121 and the first photoresist 131 may function as masks. A portion ofthe first organic functional layer 141 may be formed at a positioncorresponding to the first portion 131-1, that is, above the first anode101, and the other portion of the first organic functional layer 141 maybe formed on a second portion 131-2 of the first photoresist 131.

Like the first organic functional layer 141, the first auxiliary cathode181 may also be formed by using a vacuum deposition method. In thedeposition process, the first lift-off layer 121 and the firstphotoresist 131 may function as masks. A portion of the first auxiliarycathode 181 may be formed to cover a top surface of the first organicfunctional layer 141, and the other portion of the first auxiliarycathode 181 may be formed on the first organic functional layer 141 on asecond portion 131-2 of the first photoresist 131 other than the firstportion 131-1.

The first auxiliary cathode 181 may include the same material as that ofa cathode 180 that is a common electrode to be described below. In someimplementations, the first auxiliary cathode 181 may include a materialdifferent from that of the cathode 180. The first auxiliary cathode 181may function as a barrier for protecting the first organic functionallayer 141 from a solvent used in a subsequent lift-off process.

Referring to FIG. 5F, a lift-off process may be performed on thestructure illustrated in FIG. 5E.

The first lift-off layer 121 may include the fluoropolymer. Accordingly,a second solvent including fluorine may be used in the lift-off process.The first organic functional layer 141 may be formed and then thelift-off process may be performed. Accordingly, the second solvent mayinclude a material having a low reactivity with the first organicfunctional layer 141. Like the first solvent, the second solvent mayinclude hydrofluoroether.

When the first lift-off layer 121 formed under the second portion 131-2(see FIG. 5E) of the first photoresist 131 is lifted off, portions ofthe first organic functional layer 141 and the first auxiliary cathode181 that were formed on the second portion 131-2 of the firstphotoresist 131 may be removed. Portions of the first organic functionallayer 141 and the first auxiliary cathode 181 formed over the firstanode 101 may remain as patterns.

The self-assembled monolayer 150 formed on the pixel-defining layer 110is not removed. As described above, an adhesive strength between thesurface of the self-assembled monolayer 150 and the surface of thepixel-defining layer 110 is high due to a hydrolysis and condensationreaction between a reactive group including silicon, included in theself-assembled monolayer 150, and a surface material of thepixel-defining layer 110. Accordingly, the self-assembled monolayer 150may be well bonded to the top surface of the pixel-defining layer 110while the first lift-off layer 121 is lifted off.

After the first unit process is performed, a second unit process offorming the second organic functional layer 142, which may emits lightof a different color from that emitted by the first organic functionallayer 141, may be performed on an area where the second anode 102 islocated. The second unit process will now be described with reference toFIGS. 6A to 6F.

Referring to FIG. 6A, a second lift-off layer 122 and a secondphotoresist 132 may be sequentially formed on the structure illustratedin FIG. 5F.

The second lift-off layer 122 may include a fluoropolymer. The secondlift-off layer 122 may include the same material as that of the firstlift-off layer 121 and may be formed by using a coating method, aprinting method, or a deposition method.

The second photoresist 132 may be formed on the second lift-off layer122. The second photoresist 132, may be exposed through a secondphotomask M2 including an area M21 through which light L is transmitted,the area M21 being at a position corresponding to the second anode 102.

Referring to FIG. 6B, the second photoresist 132 may be developed. Inthe second photoresist 132, a first portion 132-1 corresponding to thesecond anode 102 may be removed and a second portion 132-2 other thanthe first portion 132-1 may remain.

Referring to FIG. 6C, the second lift-off layer 122 may be etched byusing a pattern of the first portion 132-1 of the second photoresist 132as an etch mask.

The second lift-off layer 122 includes the fluoropolymer. Accordingly, asolvent that etches the fluoropolymer may be used as an etchant. Forexample, a first solvent including fluorine may be used as the etchant.The first solvent may include hydrofluoroether.

A portion of the second lift-off layer 122 formed at a positioncorresponding to the first portion 132-1, that is, above the secondanode 102, may be etched during an etching process. The second lift-offlayer 122 may be etched by the first solvent including fluorine to forma second undercut profile UC2-1 under a boundary surface of the firstportion 132-1 of the second photoresist 132.

The self-assembled monolayer 150 may be well bonded to the top surfaceof the second anode 102 while the second lift-off layer 122 is etched.In addition, the self-assembled monolayer 150 may be well bonded to thetop surface of the pixel-defining layer 110 while the second lift-offlayer 122 is etched.

Referring to FIG. 6D, a portion of the self-assembled monolayer 150 onthe second anode 102 may be removed by performing a second plasma heattreatment on the structure illustrated in FIG. 6C.

An Si—O bond between the second anode 102 and the self-assembledmonolayer 150 may be cleanly broken by the second plasma heat treatment.Accordingly, a residue of the second lift-off layer 122 may not remainon the second anode 102.

Referring to FIG. 6E, a second organic functional layer 142 including asecond emission layer and a second auxiliary cathode 182 may besequentially formed on the structure illustrated in FIG. 6D.

The second organic functional layer 142 may further include at least oneselected from a hole injection layer, a hole transport layer, anelectron transport layer, and an electron injection layer.

The second organic functional layer 142 may be formed by using a vacuumdeposition method. In the deposition process, the second lift-off layer122 and the second photoresist 132 may function as masks. A portion ofthe second organic functional layer 142 may be formed at a positioncorresponding to the first portion 132-1, that is, above the secondanode 102, and another portion of the second organic functional layer142 may be formed on the second portion 132-2 of the second photoresist132.

Like the second organic functional layer 142, the second auxiliarycathode 182 may be formed by using a vacuum deposition method. In thedeposition process, the second lift-off layer 122 and the secondphotoresist 132 may function as masks. A portion of the second auxiliarycathode 182 may be formed to cover a top surface of the second organicfunctional layer 142, and another portion of the second auxiliarycathode 182 may be formed on the second organic functional layer 142 onthe second portion 132-2 of the second photoresist 132.

The second auxiliary cathode 182 may include the same material as thatof the cathode 180 that is a common electrode to be described below. Insome implementations, the second auxiliary cathode 182 may include amaterial different from that of the cathode 180. The second auxiliarycathode 182 may function as a barrier for protecting the second organicfunctional layer 142 from a solvent used in a subsequent lift-offprocess.

Referring to FIG. 6F, a lift-off process may be performed on thestructure illustrated in FIG. 6E.

The second lift-off layer 122 includes the fluoropolymer. Accordingly, asecond solvent including fluorine may be used in the lift-off process.The second organic functional layer 142 may be formed and then thelift-off process may be performed. Accordingly, the second solvent mayinclude a material having a low reactivity with the second organicfunctional layer 142. Like the first solvent, the second solvent mayinclude hydrofluoroether.

When the second lift-off layer 122 formed under the second portion 132-2(see FIG. 6E) of the second photoresist 132 is lifted off, portions ofthe second organic functional layer 142 and the second auxiliary cathode182 that were formed on the second portion 132-2 of the secondphotoresist 132 may be removed. Portions of the second organicfunctional layer 142 and the second auxiliary cathode 182 formed overthe second anode 102 may remain as patterns.

As described above, an adhesive strength between the self-assembledmonolayer 150 and the pixel-defining layer 110 may be sufficient suchthat the self-assembled monolayer 150 formed on the pixel-defining layer110 is not removed when the second lift-off layer 122 is lifted off.

After the second unit process is performed, a third unit process offorming the third organic functional layer 143, which may emit light ofa different color from that emitted by the first organic functionallayer 141 and the second organic functional layer 142 may be performedon an area where the third anode 103 is located. The third unit processwill now be described with reference to FIGS. 7A to 7F.

Referring to FIG. 7A, a third lift-off layer 123 and a third photoresist133 may be sequentially formed the structure illustrated in FIG. 6F.

The third lift-off layer 123 may include a fluoropolymer. The thirdlift-off layer 123 may include the same material as that of the firstand second lift-off layers 121 and 122 and may be formed by using acoating method, a printing method, or a deposition method.

The third photoresist 133 may be formed on the third lift-off layer 123.The third photoresist 133 at a position corresponding to the third anode103 may be exposed through a third photomask M3 including an area M31through which light L is transmitted.

Referring to FIG. 7B, the third photoresist 133 may be developed. In thethird photoresist 133, a first portion 133-1 corresponding to the thirdanode 103 may be removed and a second portion 133-2 other than the firstportion 133-1 may remain.

Referring to FIG. 7C, the third lift-off layer 123 may be etched byusing a pattern of the first portion 133-1 of the third photoresist 133as an etch mask.

The third lift-off layer 123 may include the fluoropolymer. Accordingly,a solvent that etches the fluoropolymer may be used as an etchant. Forexample, a first solvent including fluorine may be used as the etchant.The first solvent may include hydrofluoroether.

A portion of the third lift-off layer 123 formed at a positioncorresponding to the first portion 133-1, that is, above the third anode103, may be etched during an etching process. The third lift-off layer123 may be etched by the first solvent including fluorine to form athird undercut profile UC3-1 under a boundary surface of the firstportion 133-1 of the third photoresist 133.

The self-assembled monolayer 150 may be well bonded to the top surfaceof the third anode 103 while the third lift-off layer 123 is etched. Inaddition, the self-assembled monolayer 150 may be well bonded to the topsurface of the pixel-defining layer 110 while the third lift-off layer123 is etched.

Referring to FIG. 7D, a portion of the self-assembled monolayer 150 onthe third anode 103 may be removed by performing third plasma heattreatment on the structure illustrated in FIG. 7C.

An Si—O bond between the third anode 103 and the self-assembledmonolayer 150 may be cleanly broken by the third plasma heat treatment.Accordingly, a residue of the third lift-off layer 123 may not remain onthe third anode 103.

Referring to FIG. 7E, a third organic functional layer 143 including athird emission layer and a third auxiliary cathode 183 may besequentially formed on the structure illustrated in FIG. 7D.

The third organic functional layer 143 may further include at least oneselected from a hole injection layer, a hole transport layer, anelectron transport layer, and an electron injection layer.

The third organic functional layer 143 may be formed by using a vacuumdeposition method. In the deposition process, the third lift-off layer123 and the third photoresist 133 may function as masks. A portion ofthe third organic functional layer 143 is formed at a positioncorresponding to the first portion 133-1, that is, above the third anode103, and another portion of the third organic functional layer 143 maybe formed on the second portion 133-2 of the third photoresist 133.

Like the third organic functional layer 143, the third auxiliary cathode183 may be formed by using a vacuum deposition method. In the depositionprocess, the third lift-off layer 123 and the third photoresist 133 mayfunction as masks. A portion of the third auxiliary cathode 183 may beformed to cover a top surface of the third organic functional layer 143,and another portion of the third auxiliary cathode 183 may be formed onthe third organic functional layer 143 on the second portion 133-2 ofthe third photoresist 133.

The third auxiliary cathode 183 may include the same material as that ofthe cathode 180 that is a common electrode to be described below. Insome implementations, the third auxiliary cathode 183 may include amaterial different from that of the cathode 180. The third auxiliarycathode 183 may function as a barrier for protecting the third organicfunctional layer 143 from a solvent used in a subsequent lift-offprocess.

Referring to FIG. 7F, a lift-off process is performed on the structureillustrated in FIG. 7E.

The third lift-off layer 123 may include the fluoropolymer. Accordingly,a second solvent including fluorine may be used in the lift-off process.The third organic functional layer 143 may be formed and then thelift-off process is performed. Accordingly, the second solvent mayinclude a material having a low reactivity with the third organicfunctional layer 143. Like the first solvent, the second solvent mayinclude hydrofluoroether.

When the third lift-off layer 123 formed under the second portion 133-2(see FIG. 7E) of the third photoresist 133 is lifted off, portions ofthe third organic functional layer 143 and the third auxiliary cathode183 that were formed on the second portion 133-2 of the thirdphotoresist 133 may be removed, and portions of the third organicfunctional layer 143 and the third auxiliary cathode 183 formed over thethird anode 103 may remain as patterns.

As described above, an adhesive strength between the self-assembledmonolayer 150 and the pixel-defining layer 110 may be sufficient suchthat the self-assembled monolayer 150 formed on the pixel-defining layer110 is not removed when the third lift-off layer 123 is lifted off.

The first, second, and third organic functional layers 141, 142, and 143may emit light of different colors. When the light of different colorsemitted from the first to third organic functional layers 141, 142, and143 is mixed, white light may be formed. For example, the first, second,and third organic functional layers 141, 142, and 143 may emit redlight, green light, and blue light, respectively. For example, the firstto third organic functional layers 141, 142, and 143 may be elements ofsub-pixels constituting a unit pixel of the organic light-emittingdisplay apparatus 1.

The organic light-emitting display apparatus 1 illustrated in FIG. 1 mayrepresent one unit pixel. Embodiments may also be applied to an organiclight-emitting display apparatus including a plurality of unit pixelsthat are the same as the unit pixel illustrated in FIG. 1. For example,a plurality of first organic functional layers 141, which emit a firstcolor, may be simultaneously formed as first sub-pixels by using thefirst unit process. A plurality of second organic functional layers 142,which emit a second color, may be simultaneously formed as secondsub-pixels by using the second unit process. A plurality of thirdorganic functional layers 143, which emit a third color, may besimultaneously formed as third sub-pixels by using the third unitprocess. Through the first to third unit processes, full color may berealized.

In the present embodiment, when a self-assembled monolayer is formedbetween an anode and a lift-off layer without the formation of thelift-off layer directly on the anode, the self-assembled monolayer mayprevent a residual film of the lift-off layer from being left on theanode, and thus deterioration of the organic light-emitting displayapparatus 1 may be prevented.

Hereinafter, a method of manufacturing an organic light-emitting displayapparatus 4 according to a comparative example is described withreference to FIGS. 18A to 20E.

FIGS. 18A to 18E illustrate cross-sectional views for explaining a firstunit process of the organic light-emitting display apparatus 4 accordingto the comparative example. FIGS. 19A to 19E illustrate cross-sectionalviews for explaining a second unit process of the organic light-emittingdisplay apparatus 4 according to the comparative example. FIGS. 20A to20E illustrate cross-sectional views for explaining a third unit processof the organic light-emitting display apparatus 4 according to thecomparative example.

Referring to FIG. 18A, a first lift-off layer 121 including afluoropolymer is formed above a substrate 100 on which first to thirdanodes 101 to 103 and a pixel-defining layer 110 covering end portionsof the first to third anodes 101 to 103 are formed, and a firstphotoresist 131 is formed on the first lift-off layer 121. The firstphotoresist 131 at a position corresponding to a first anode 101 isexposed through a first photomask M1 including an area M11 through whichlight L is transmitted.

Referring to FIG. 18B, the first photoresist 131 is patterned. The firstphotoresist 131 that is exposed and developed is removed at the firstportion 131-1 corresponding to the first anode 101 and remains at asecond portion 131-2 other than the first portion 131-1.

Referring to FIG. 18C, the first lift-off layer 121 is etched by using apattern of the first photoresist 131 of FIG. 18B as an etch mask andusing a first solvent (not shown) including fluorine. During an etchingprocess, a portion of the first lift-off layer 121 formed at a positioncorresponding to the first portion 131-1, that is, on the first anode101, is etched. The first lift-off layer 121 is etched to form a firstundercut profile UC1 under a boundary surface of the first portion 131-1of the first photoresist 131. When the first lift-off layer 121 isstripped after the etching process is performed, an undesirable residueof the first lift-off layer 121 may remain on the first anode 101.

Referring to FIG. 18D, a first organic functional layer 141 and a firstauxiliary cathode 181 are sequentially formed on a structure of FIG.18C.

Referring to FIG. 18E, a first lift-off process is performed such thatremaining portions of the first lift-off layer 121 are entirely removed,and as a result, the first organic functional layer 141 and the firstauxiliary cathode 181 remain as patterns on the first anode 101.

After the first unit process is completed, the second unit process isperformed on an area at which a second anode 102 is located.

Referring to FIG. 19A, a second lift-off layer 122 and a secondphotoresist 132 are sequentially formed on a structure of FIG. 18E.

Referring to FIG. 19B, the second photoresist 132 is patterned. Thesecond photoresist 132 that is exposed and developed is patterned to beremoved at a first portion 132-1 corresponding to the second anode 102and remain at a second portion 132-2 other than the first portion 132-1.

Referring to FIG. 19C, the second lift-off layer 122 is etched by usinga pattern of the second photoresist 132 of FIG. 19B as an etch mask andusing the first solvent (not shown) including fluorine. During anetching process, a portion of the second lift-off layer 122 formed at aposition corresponding to the first portion 132-1, that is, on thesecond anode 102, is etched. The second lift-off layer 122 is etched toform a second undercut profile UC2 under a boundary surface of the firstportion 132-1 of the second photoresist 132. When the second lift-offlayer 122 is stripped after the etching process is performed, anundesirable residue of the second lift-off layer 122 may remain on thesecond anode 102.

Referring to FIG. 19D, a second organic functional layer 142 and anauxiliary cathode 182 are sequentially formed on a structure of FIG.19C.

Referring to FIG. 19E, a second lift-off process is performed such thatremaining portions of the second lift-off layer 122 are entirelyremoved, and as a result, the second organic functional layer 142 andthe second auxiliary cathode 182 remain as patterns on the second anode102.

After the second unit process is completed, the third unit process isperformed on an area at which a third anode 103 is located.

Referring to FIG. 20A, a third lift-off layer 123 and a thirdphotoresist 133 are sequentially formed on a structure of FIG. 19E.

Referring to FIG. 20B, the third photoresist 132 is patterned. The thirdphotoresist 133 that is exposed and developed is patterned to be removedat a first portion 133-1 corresponding to the third anode 103 and remainat a second portion 133-2 other than the first portion 133-1.

Referring to FIG. 20C, the third lift-off layer 123 is etched by using apattern of the third photoresist 133 of FIG. 20B as an etch mask andusing the first solvent (not shown) including fluorine. During anetching process, a portion of the third lift-off layer 123 formed at aposition corresponding to the first portion 133-1, that is, on the thirdanode 103, is etched. The third lift-off layer 123 is etched to form athird undercut profile UC3 under a boundary surface of the first portion133-1 of the third photoresist 133. When the third lift-off layer 123 isstripped after the etching process is performed, an undesirable residueof the third lift-off layer 123 may remain on the third anode 102.

Referring to FIG. 20D, a third organic functional layer 143 and a thirdauxiliary cathode 183 are sequentially formed on a structure of FIG.20C.

Referring to FIG. 20E, a third lift-off process is performed such thatremaining portions of the third lift-off layer 123 are entirely removed,and as a result, the third organic functional layer 143 and the thirdauxiliary cathode 183 remain as patterns on the third anode 103.

That is, according to the comparative example, when a lift-off layer isformed directly on an anode and then is patterned, it may not bepossible to prevent a residual film of the lift-off layer from remainingon the anode.

Hereinafter, with reference to FIGS. 8 to 14F, an organic light-emittingdisplay apparatus 2 according to an embodiment and a method ofmanufacturing the organic light-emitting display apparatus 2 aredisclosed.

FIG. 8 illustrates a cross-sectional view of an organic light-emittingdisplay apparatus 2 according to an embodiment, and FIG. 9 illustrates aplan view of a portion of the organic light-emitting display apparatus 2according to the embodiment.

Referring to FIGS. 8 and 9, a plurality of anodes including a firstanode 101, a second anode 102, and a third anode 103 that are spacedapart from each other on a substrate 100 may be provided. First to thirdorganic functional layers 141, 142, and 143 including first to thirdemission layers may be respectively located on the first to third anodes101, 102, and 103. First to third auxiliary cathodes 181, 182, and 183including a conductive material may be respectively located on the firstto third organic functional layers 141, 142, and 143. An integrallyformed common electrode 180 may be located on the first to thirdauxiliary cathodes 181, 182, and 183.

In the organic light-emitting display apparatus 2 according to theembodiment, a self-assembled monolayer 150 may surround the first tothird anodes 101, 102 and 103, and a pixel-defining layer 110 may beformed on the self-assembled monolayer 150. For example, portions of theself-assembled monolayer 150 may be under the pixel defining layer. Inthis embodiment, the self-assembled monolayer 150 may overlap endportions of the first to third anodes 101, 102, and 103 by apredetermined thickness D2. Hereinafter, descriptions of this embodimentthat are the same as those of the above-described embodiment illustratedin FIG. 1 may be omitted.

Referring to FIG. 10, a plurality of anodes including the first anode101, the second anode 102, and the third anode 103 may be formed on thesubstrate 100, and the self-assembled monolayer 150 may be formed overthe plurality of anodes.

Referring to FIG. 11, the pixel-defining layer 110 may be formed tosurround edges of the first anode 101, the second anode 102, and thethird anode 103. In this case, an end portion of the pixel-defininglayer 110 may overlap an end portion of the self-assembled monolayer150. The self-assembled monolayer 150 may include a fluorine-containingfunctional group and a hydrolyzable reactive group.

Referring to FIG. 12A, a first lift-off layer 121 and a firstphotoresist 131 may be sequentially formed on the structure illustratedin FIG. 11.

The first lift-off layer 121 may include a fluoropolymer and may beformed by using a coating method, a printing method, or a depositionmethod. The first photoresist 131 may be formed on the first lift-offlayer 121. The first photoresist 131 at a position corresponding to thefirst anode 101 may be exposed through a first photomask M1 including anarea M11 through which light L is transmitted.

The fluorine-containing functional group of the self-assembled monolayer150 that closely contacts the first lift-off layer 121 may have a smalldifference in surface energy with respect to the first lift-off layer121, and thus the first lift-off layer 121 may be uniformly formed onthe self-assembled monolayer 150.

Referring to FIG. 12B, the first photoresist 131 may be developed. Inthe first photoresist 131 that is developed, a first portion 131-1corresponding to the first anode 101 may be removed and a second portion131-2 other than the first portion 131-1 may remain.

Referring to FIG. 12C, the first lift-off layer 121 may be etched byusing a pattern of the first portion 131-1 of the first photoresist 131as an etch mask. During an etching process, a portion of the firstlift-off layer 121 formed at a position corresponding to the firstportion 131-1, that is, above the first anode 101, may be etched. Thefirst lift-off layer 121 may be etched by a first solvent includingfluorine to form a first undercut profile UC1-1 under a boundary surfaceof the first portion 131-1 of the first photoresist 131.

The self-assembled monolayer 150 may be well bonded to the top surfaceof the first anode 101 while the first lift-off layer 121 is etched.

Referring to FIG. 12D, a portion of the self-assembled monolayer 150 onthe first anode 101 may be removed by performing first plasma heattreatment on the structure illustrated in FIG. 12C.

The Si—O bond between the first anode 101 and the self-assembledmonolayer 150 shown in FIG. 21 may be cleanly broken by the first plasmaheat treatment.

Referring to FIG. 12E, a first organic functional layer 141 including afirst emission layer and a first auxiliary cathode 181 are sequentiallyformed on the structure illustrated in FIG. 12D. A portion of the firstorganic functional layer 141 may be formed at a position correspondingto the first portion 131-1, that is, above the first anode 101, andanother portion of the first organic functional layer 141 may be formedon the second portion 131-2 of the first photoresist 131. A portion ofthe first auxiliary cathode 181 may be formed to cover a top surface ofthe first organic functional layer 141, and another portion of the firstauxiliary cathode 181 may be formed on the first organic functionallayer 141 on the second portion 131-2 of the first photoresist 131 otherthan the first portion 131-1.

Referring to FIG. 12F, a lift-off process may be performed on thestructure illustrated in FIG. 12E. When the first lift-off layer 121formed under the second portion 131-2 (see FIG. 12E) of the firstphotoresist 131 is lifted off, portions of the first organic functionallayer 141 and the first auxiliary cathode 181 formed over the secondportion 131-2 of the first photoresist 131 may be removed, and portionsof the first organic functional layer 141 and the first auxiliarycathode 181 formed over the first anode 101 may remain as patterns.

After the first unit process is performed, a second unit process offorming the second organic functional layer 142 that emits light of adifferent color from a color of light emitted by the first organicfunctional layer 141 may be performed on an area where the second anode102 is located. The second unit process will now be described withreference to FIGS. 13A to 13F.

Referring to FIG. 13A, a second lift-off layer 122 and a secondphotoresist 132 may be sequentially formed on the structure illustratedin FIG. 12F. The second photoresist 132 at a position corresponding tothe second anode 102 may be exposed through a second photomask M2including an area M21 through which light L is transmitted.

The fluorine-containing functional group of the self-assembled monolayer150 that closely contacts the second lift-off layer 122 may have a smalldifference in surface energy with respect to the second lift-off layer122, and thus the second lift-off layer 122 may be uniformly formed onthe self-assembled monolayer 150.

Referring to FIG. 13B, the second photoresist 132 may be developed. Inthe second photoresist 132, a first portion 132-1 corresponding to thesecond anode 102 is removed and a second portion 132-2 other than thefirst portion 132-1 may remain.

Referring to FIG. 13C, the second lift-off layer 122 may be etched byusing a pattern of the first portion 132-1 of the second photoresist 132as an etch mask. A portion of the second lift-off layer 122 formed at aposition corresponding to the first portion 132-1, that is, above thesecond anode 102, may be etched during an etching process. The secondlift-off layer 122 may be etched by the first solvent including fluorineto form a second undercut profile UC2-1 under a boundary surface of thefirst portion 132-1 of the second photoresist 132. The self-assembledmonolayer 150 may be well bonded to the top surface of the second anode102 while the second lift-off layer 122 is etched.

Referring to FIG. 13D, a portion of the self-assembled monolayer 150 onthe second anode 102 may be removed by performing a second plasma heattreatment PT2 on the structure illustrated in FIG. 13C. An Si—O bondbetween the second anode 102 and the self-assembled monolayer 150 may becleanly broken by the second plasma heat treatment.

Referring to FIG. 13E, a second organic functional layer 142 including asecond emission layer and a second auxiliary cathode 182 may besequentially formed on the structure illustrated in FIG. 13D. A portionof the second organic functional layer 142 may be formed at a positioncorresponding to the first portion 132-1, that is, above the secondanode 102, and the other portion of the second organic functional layer142 may be formed on the second portion 132-2 of the second photoresist132. A portion of the second auxiliary cathode 182 may be formed tocover a top surface of the second organic functional layer 142, and theother portion of the second auxiliary cathode 182 may be formed on thesecond organic functional layer 142 on the second portion 132-2 of thesecond photoresist 132 other than the first portion 132-1.

Referring to FIG. 13F, a lift-off process may be performed on astructure illustrated in FIG. 13E. When the second lift-off layer 122formed under the second portion 132-2 of the second photoresist 132 islifted off, portions of the second organic functional layer 142 and thesecond auxiliary cathode 182 formed over the second portion 132-2 of thesecond photoresist 132 may be removed, and portions of the secondorganic functional layer 142 and the second auxiliary cathode 182 formedover the second anode 102 may remain as patterns.

After the second unit process is performed, a third unit process offorming the third organic functional layer 143 that emits light of adifferent color from a color of light emitted by the first and secondorganic functional layers 141 and 142 may be performed on an area wherethe third anode 103 is located. The third unit process will now bedescribed with reference to FIGS. 14A to 14F.

Referring to FIG. 14A, a third lift-off layer 123 and a thirdphotoresist 133 may be sequentially formed on the structure illustratedin FIG. 13F. The third photoresist 133 at a position corresponding tothe third anode 103 may be exposed through a third photomask M3including an area M31 through which light L is transmitted.

The fluorine-containing functional group of the self-assembled monolayer150 that closely contacts the third lift-off layer 123 may have a smalldifference in surface energy with respect to the third lift-off layer123, and thus the third lift-off layer 123 may be uniformly formed onthe self-assembled monolayer 150.

Referring to FIG. 14B, the third photoresist 133 may be developed. Inthe third photoresist 133, a first portion 133-1 corresponding to thethird anode 103 may be removed and a second portion 133-2 other than thefirst portion 133-1 may remain.

Referring to FIG. 14C, the third lift-off layer 123 may be etched byusing a pattern of the first portion 133-1 of the third photoresist 133as an etch mask. A portion of the third lift-off layer 123 formed at aposition corresponding to the first portion 133-1, that is, above thethird anode 103, may be etched during an etching process. The thirdlift-off layer 123 may be etched by the first solvent including fluorineto form a third undercut profile UC3-1 under a boundary surface of thefirst portion 133-1 of the third photoresist 133. The self-assembledmonolayer 150 may be well bonded to the top surface of the third anode103 while the third lift-off layer 123 is etched.

Referring to FIG. 14D, a portion of the self-assembled monolayer 150 onthe third anode 103 may be removed by performing a third plasma heattreatment on a structure illustrated in FIG. 14C. An Si—O bond betweenthe third anode 103 and the self-assembled monolayer 150 may be cleanlybroken by the third plasma heat treatment.

Referring to FIG. 14E, a third organic functional layer 143 including athird emission layer and a third auxiliary cathode 183 may besequentially formed the a structure illustrated in FIG. 14D. A portionof the third organic functional layer 143 may be formed at a positioncorresponding to the first portion 133-1, that is, above the third anode103, and another portion of the third organic functional layer 143 maybe formed on the second portion 133-2 of the third photoresist 133. Aportion of the third auxiliary cathode 183 may be formed to cover a topsurface of the third organic functional layer 143, and another portionof the third auxiliary cathode 183 may be formed on the third organicfunctional layer 143 on the second portion 133-2 of the thirdphotoresist 133 other than the first portion 133-1.

Referring to FIG. 14F, a lift-off process may be performed on thestructure illustrated in FIG. 14E. When the third lift-off layer 123formed under the second portion 133-2 of the third photoresist 133 islifted off, portions of the third organic functional layer 143 and thethird auxiliary cathode 183 formed over the second portion 133-2 of thethird photoresist 133 may be removed, and portions of the third organicfunctional layer 143 and the third auxiliary cathode 183 formed over thethird anode 103 may remain as patterns.

Hereinafter, a method for manufacturing an organic light-emittingdisplay apparatus 3 according to an embodiment will be briefly describedwith reference to FIGS. 15A to 17E.

The present embodiment differs from the previous embodiments in that aself-assembled monolayer is used as a lift-off layer withoutindependently using the lift-off layer and the self-assembled monolayer.

FIGS. 15A to 15E illustrate cross-sectional views for explaining a firstunit process of an organic light-emitting display apparatus 3 accordingto the embodiment.

Referring to FIG. 15A, first to third anodes 101, 102, and 103 may beformed on a substrate 101, and a pixel defining layer 110 defining aplurality of pixels may be formed to cover end portions of the first tothird anodes 101, 102, and 103. After the pixel-defining layer 110 isformed, a first self-assembled monolayer 151 may be formed. A firstphotoresist 131 may be formed on the first self-assembled monolayer 151.

The first self-assembled monolayer 151 may include a hydrolyzablereactive group and a fluorine-containing functional group. In thepresent embodiment, as described above, the first photoresist 131 may beformed on the first self-assembled monolayer 151. The first photoresist131 may, but need not, include a fluoropolymer. Accordingly, the firstself-assembled monolayer 151 of the present embodiment need notnecessarily include a fluorine-containing functional group as in theabove-described embodiment. For example, the first self-assembledmonolayer 151 may further include octadecyltrichlorosilane (OTS),dichlorodimethylsilane (DDMS), tetraethoxysilane (TEOS), or the like.

The first photoresist 131 at a position corresponding to the first anode101 may be exposed through a first photomask M1 including an area M11through which light L is transmitted. The fluorine-containing functionalgroup of the first self-assembled monolayer 151 that closely contactsthe first photoresist 131 may use a material having a small differencein surface energy with respect to a photosensitive material contained inthe first photoresist 131.

Referring to FIG. 15B, the first photoresist 131 may be developed. Inthe first photoresist 131 that is developed, a first portion 131-1corresponding to the first anode 101 may removed and a second portion131-2 other than the first portion 131-1 may remain.

Referring to FIG. 15C, a portion of the first self-assembled monolayer151 on the first anode 101 may be removed by performing a first plasmaheat treatment PT1 on the structure illustrated in FIG. 15B. An Si—Obond between the first anode 101 and the first self-assembled monolayer151 may be cleanly broken by the first plasma heat treatment PT1.

Referring to FIG. 15D, a first organic functional layer 141 including afirst emission layer and a first auxiliary cathode 181 may besequentially formed on the structure illustrated in FIG. 15C. A portionof the first organic functional layer 141 may be formed at a positioncorresponding to the first portion 131-1, that is, above the first anode101, and another portion of the first organic functional layer 141 maybe formed on the second portion 131-2 of the first photoresist 131. Aportion of the first auxiliary cathode 181 may be formed to cover a topsurface of the first organic functional layer 141, and another portionof the first auxiliary cathode 181 may be formed on the first organicfunctional layer 141 on the second portion 131-2 of the firstphotoresist 131 other than the first portion 131-1.

Referring to FIG. 15E, a lift-off process may be performed on thestructure illustrated in FIG. 15D. When the first photoresist 131 islifted off, portions of the first organic functional layer 141 and thefirst auxiliary cathode 181 formed over the second portion 131-2 of thefirst photoresist 131 may be removed, and portions of the first organicfunctional layer 141 and the first auxiliary cathode 181 formed over thefirst anode 101 may remain as patterns. The first self-assembledmonolayer 151 located between the pixel-defining layer 110 and the firstphotoresist 131 may also be removed.

FIGS. 16A to 16E illustrate cross-sectional views for explaining asecond unit process of the organic light-emitting display apparatus 3according to this embodiment.

Referring to FIG. 16A, a second self-assembled monolayer 152 and asecond photoresist 132 may be sequentially formed on the structureillustrated in FIG. 15E. The second photoresist 132 at a positioncorresponding to the second anode 102 may be exposed through a secondphotomask M2 including an area M21 through which light L is transmitted.A functional group of the second self-assembled monolayer 152 thatclosely contacts the second photoresist 132 may use a material having asmall difference in surface energy with respect to a photosensitivematerial contained in the second photoresist 132.

Referring to FIG. 16B, the second photoresist 132 may be developed. Inthe second photoresist 132 that is developed, a first portion 132-1corresponding to the second anode 102 may be removed and a secondportion 132-2 other than the first portion 132-1 may remain.

Referring to FIG. 16C, a portion of the second self-assembled monolayer152 on the second anode 102 may be removed by performing second plasmaheat treatment PT2 on a structure illustrated in FIG. 16B. An Si—O bondbetween the second anode 102 and the second self-assembled monolayer 152may be cleanly broken by the second plasma heat treatment PT2.

Referring to FIG. 16D, a second organic functional layer 142 including afirst emission layer and a second auxiliary cathode 182 may besequentially formed on the structure illustrated in FIG. 16C. A portionof the second organic functional layer 142 may be formed at a positioncorresponding to the first portion 132-1, that is, above the secondanode 102, and another portion of the second organic functional layer142 may be formed on the second portion 132-2 of the second photoresist132. A portion of the second auxiliary cathode 182 may be formed tocover a top surface of the second organic functional layer 142, andanother portion of the second auxiliary cathode 182 may be formed on thesecond organic functional layer 142 on the second portion 132-2 of thesecond photoresist 132 other than the first portion 132-1.

Referring to FIG. 16E, a lift-off process is performed on the structureillustrated in FIG. 16D. When the second photoresist 132 is lifted off,portions of the second organic functional layer 142 and the secondauxiliary cathode 182 formed over the second portion 132-2 of the secondphotoresist 132 may be removed, and portions of the second organicfunctional layer 142 and the second auxiliary cathode 182 formed overthe second anode 102 may remain as patterns. The second self-assembledmonolayer 152 located between the pixel-defining layer 110 and thesecond photoresist 132 may also be removed.

FIGS. 17A to 17E illustrate cross-sectional views for explaining a thirdunit process of the organic light-emitting display apparatus 3 accordingto this embodiment.

The third unit process is similar to the second unit process describedwith reference to FIGS. 16A to 16E, except that a third self-assembledmonolayer 153 is formed and finally removed, and thus, a detaileddescription of the third unit process will not be repeated.

Although not shown in the drawings, the organic light-emitting displayapparatuses described above may further include a sealing member forsealing an organic emission layer. The sealing member may include aglass substrate, a metal foil, a thin film encapsulating layer in whichan inorganic layer and an organic layer are mixed, or the like.

By way of summation and review, embodiments provide an organiclight-emitting display apparatus with increased resolution and reduceddefects and cost. Embodiments further provide a method of manufacturingthe organic light-emitting display.

According to one or more embodiments as described above, an emissionlayer is formed without using a fine metal mask (FMM). Accordingly, ahigh resolution display panel may be formed.

A self-assembled monolayer may be formed between an anode and a lift-offlayer. Accordingly, the self-assembled monolayer may prevent a residueof lift-off layer from remaining on the anode. Thus, quality of anorganic light-emitting display apparatuses according to the embodimentsmay be improved.

Example embodiments have been disclosed herein, and although specificterms are employed, they are used and are to be interpreted in a genericand descriptive sense only and not for purpose of limitation. In someinstances, as would be apparent to one of ordinary skill in the art asof the filing of the present application, features, characteristics,and/or elements described in connection with a particular embodiment maybe used singly or in combination with features, characteristics, and/orelements described in connection with other embodiments unless otherwisespecifically indicated. Accordingly, it will be understood by those ofskill in the art that various changes in form and details may be madewithout departing from the spirit and scope thereof as set forth in thefollowing claims.

What is claimed is:
 1. An organic light-emitting display apparatus,comprising: a substrate; a first first electrode on the substrate; afirst organic functional layer on the first first electrode, the firstorganic functional layer including a first emission layer; a firstsecond electrode on the first organic functional layer; a second firstelectrode on the substrate, the second first electrode being spacedapart from the first first electrode; a second organic functional layeron the second first electrode, the second organic functional layerincluding a second emission layer; a second second electrode on thesecond organic functional layer; and a self-assembled layer between thefirst organic functional layer and the second organic functional layer,the self-assembled layer containing fluorine.
 2. The organiclight-emitting display apparatus as claimed in claim 1, wherein a colorof light emitted from the first emission layer is different from a colorof light emitted from the second emission layer.
 3. The organiclight-emitting display apparatus as claimed in claim 1, wherein each ofthe first organic functional layer and the second organic functionallayer further includes at least one of a hole injection layer, a holetransport layer, an electron transport layer, and an electron injectionlayer.
 4. The organic light-emitting display apparatus as claimed inclaim 1, further comprising a pixel-defining layer including aninsulating layer and covering an edge of the first first electrode andan edge of the second first electrode.
 5. The organic light-emittingdisplay apparatus as claimed in claim 4, wherein an edge portion of thefirst organic functional layer and an edge portion of the second organicfunctional layer are on an inclined surface of the pixel-defining layer.6. The organic light-emitting display apparatus as claimed in claim 4,wherein the self-assembled layer is on the pixel-defining layer andsurrounds the first organic functional layer and the second organicfunctional layer.
 7. The organic light-emitting display apparatus asclaimed in claim 6, wherein the self-assembled layer is spaced apartfrom end portions of the first organic functional layer and the secondorganic functional layer by a preset gap.
 8. The organic light-emittingdisplay apparatus as claimed in claim 4, wherein the self-assembledlayer is under the pixel-defining layer and surrounds peripheries of thefirst first electrode and the second first electrode.
 9. The organiclight-emitting display apparatus as claimed in claim 8, wherein theself-assembled layer overlaps end portions of the first first electrodeand the second first electrode.
 10. The organic light-emitting displayapparatus as claimed in claim 1, wherein the self-assembled layerincludes a fluorocarbon group (—CF₃).
 11. The organic light-emittingdisplay apparatus as claimed in claim 1, wherein the first firstelectrode and the second first electrode include a conductive oxide. 12.The organic light-emitting display apparatus as claimed in claim 9,wherein the first first electrode and the second first electrode includeat least one of indium tin oxide, indium zinc oxide, zinc oxide, indiumoxide, indium gallium oxide, and aluminum zinc oxide.
 13. The organiclight-emitting display apparatus as claimed in claim 1, furthercomprising a common electrode integrally formed on the first secondelectrode and the second second electrode.
 14. A method of manufacturingan organic light-emitting display apparatus, the method comprising:forming a first first electrode and a second first electrode on asubstrate so as to be spaced apart from each other; forming aself-assembled layer containing fluorine on the first first electrodeand the second first electrode; sequentially forming a first lift-offlayer and a first photoresist on the self-assembled layer; removing aportion of the first lift-off layer and a portion of the firstphotoresist in an area corresponding to the first first electrode andallowing the self-assembled layer to remain; removing a portion of theself-assembled layer on the first first electrode by performing firstplasma heat treatment; and sequentially forming, on the first firstelectrode, a first organic functional layer and a first secondelectrode, wherein the first organic functional layer includes a firstemission layer, and lifting off a remaining portion of the firstlift-off layer.
 15. The method as claimed in claim 14, wherein the firstlift-off layer has a fluorine content ranging from 20 wt % to 60 wt %.16. The method as claimed in claim 14, wherein the first organicfunctional layer and the first second electrode are formed by adeposition process.
 17. The method as claimed in claim 14, whereinremoving the portion of the first photoresist includes performing aphotolithography process.
 18. The method as claimed in claim 14, whereinthe first lift-off layer is etched and removed by using a first solventcontaining fluorine.
 19. The method as claimed in claim 14, wherein theself-assembled layer is formed by a vapor deposition method.
 20. Themethod as claimed in claim 14, wherein the self-assembled layer includesa hydrolyzable reactive group and a fluorine-containing functionalgroup.
 21. The method as claimed in claim 14, further comprising:sequentially forming a second lift-off layer and a second photoresistafter lifting off the remaining portion of the first lift-off layer;removing a portion of the second lift-off layer and a portion of thesecond photoresist in an area corresponding to the second firstelectrode and allowing the self-assembled layer to remain; removing aportion of the self-assembled layer on the second first electrode byperforming second plasma heat treatment; sequentially forming a secondorganic functional layer and the second second electrode on the secondfirst electrode, wherein the second organic functional layer includes asecond emission layer, and lifting off a remaining portion of the secondlift-off layer.
 22. The method as claimed in claim 14, furthercomprising forming, between the first first electrode and the secondfirst electrode, a pixel-defining layer including an insulating layer.23. The method as claimed in claim 22, wherein the self-assembled layeris formed on the pixel-defining layer.
 24. The method as claimed inclaim 22, wherein the self-assembled layer is formed under thepixel-defining layer.
 25. The method as claimed in claim 21, furthercomprising forming a common electrode in an integral form on the firstsecond electrode and the second second electrode.
 26. A method ofmanufacturing an organic light-emitting display apparatus, the methodcomprising: forming a first first electrode and a second first electrodeon a substrate so as to be spaced apart from each other; forming a firstself-assembled layer on the first first electrode and the second firstelectrode; forming a first photoresist on the first self-assembledlayer; removing a portion of the first photoresist in an areacorresponding to the first first electrode and allowing the firstself-assembled layer to remain; removing a portion of the firstself-assembled layer on the first first electrode by performing firstplasma heat treatment; and sequentially forming a first organicfunctional layer and a first second electrode on the first firstelectrode, wherein the first organic functional layer includes a firstemission layer, and lifting off a remaining portion of the firstphotoresist and a remaining portion of the first self-assembled layer.